Chevrolet 2010 Avalanche Owner's Manual page 226

Press to turn the outside air mode
on. An indicator light comes on to show that outside air
is on. Air from outside the vehicle is circulated
throughout the vehicle. The outside air mode can be
used with all modes, but it cannot be used with the
recirculation mode. Pressing this button again will
cancel the recirculation mode.
Press to turn the recirculation
mode on or off. An indicator light comes on to show that
recirculation is on.
This mode recirculates and helps to quickly cool the
air inside the vehicle. It can be used to help prevent
outside air and odors from entering the vehicle.
The recirculation mode cannot be used with floor,
defrost, or defogging modes. If recirculation is selected
while in one of those modes, the indicator flashes three
times and turns off. The air conditioning compressor will
also come on when this mode is activated. While in
recirculation mode the windows may fog when the
weather is cold and damp. To clear the fog, select either
the defog or defrost mode and increase the fan speed.
The recirculation mode can also be turned off by turning
off the engine.
4-18
The rear window defogger uses a warming grid to
remove fog from the rear window.
right knob to turn the rear window defogger on or off.
The system automatically turns off several minutes after
it has been activated. The defogger can also be turned
off by turning off the engine. Do not drive the vehicle
until all the windows are clear.
For vehicles with heated outside rearview mirrors, the
mirrors will heat to help clear fog or frost from the
surface of the mirror when the rear window defog button
is pressed.
Press this button on the